1. Field of the Invention
The present invention relates in general to a so-called double cassette tape player having a pair of tape decks, and more particularly to a mechanism for retaining one of the two tape decks in the double cassette tape player in its inoperative position, while both tape decks being driven by a single power source.
2. Description of the Prior Art
The double cassette tape player has been known in the art, which comprises a pair of tape decks, each being designed substantially as a single type tape player, and a drive mechanism for driving the two decks. The tape player of this type is particularly useful for dubbing from a recorded tape cassette on one deck (sub-deck) to a raw tape cassette on the other deck (main deck). In response to single key operation by the user, both tape decks are driven synchronously. Of course, the sub-deck carrying the recorded tape cassette operates for playback and the main deck carrying the raw tape cassette operates for recording. Such dubbing operation with the double cassette tape player should be compared with the same operation using two separate cassette tape player, which needs connection between the two players and synchronous key operation on both players.
With the double cassette tape player, both tape decks should be driven simultaneously during the dubbing operation. Apart from dubbing, however, only the main deck is driven, the sub-deck being made inoperative. For example, should both tape decks, each carrying the recorded tape cassette, be driven simultaneously in response to the user's key operation which commands playback, both tape decks would run for playback of different music data. To cope with this problem, the double cassette tape player should be designed such that the sub-deck is used only for dubbing and is made inoperative when another kind of operation is designated by the user.
This requirement can be fulfilled by employing separate drive sources for individually driving the two tape decks. This requires two motors which should be controlled by separate drive control circuits. It should raise a manufacturing cost and needs a larger space for mounting the motors and circuits. Moreover, a synchronizer is additionally required to drive the two motors synchronously at the time of dubbing operation, which complicates the overall construction and arrangement and further increases the manufacturing cost of the double cassette tape player.
One of the inventors have already invented the cassette tape drive mechanism in a single type cassette tape player, which is patented as U.S. Pat. No. 4,935,831, the disclosure of which is hereby incorporated for reference. This drive mechanism has an idle gear rotatable on a pin at the leading end position of a rotary arm that is driven by a motor. The idle gear will mesh with a semi-circular inner gear. When the idle gear separates from one end of the inner gear, it then meshes with a forward or reverse reel drive gear so that a cassette tape carried on the tape player is to run in a forward or reverse direction. Movement of the idle gear toward the end of the inner gear will also move a head plate toward its operative position where one of pinch rollers is in press-contact with a corresponding capstan, between which the cassette tape travels in the forward or reverse direction.
Such drive mechanism is simple in construction and arrangement and can be manufactured at a relatively low cost. However, when this drive mechanism is applied to each of the tape decks in the double cassette tape player with a single drive source or motor, as described above, both tape decks are always driven simultaneously by the single motor, which might cause any trouble and disadvantage at the time of operation other than dubbing.
Accordingly, it is desirable to provide a mechanism for retaining one tape deck in its inoperative position, when so demanded, in a double cassette tape player in which both tape decks may be simultaneously driven by a single drive source through the above-described drive mechanism proposed by the inventor.